| Avermectin antibiotics (AVMs) with novel chemical structure, unique mechanism of action, great insecticidal activity and broad insecticidal spectrum, have strong ability of expelling and killing nematodes and Arthropods in vitro. AVMs have made a significant contribution on crop protection, animal and human health, which is one of the most widely used anti-parasite drugs. Avermectins include Avermectin (AVM), Ivermectin (IVM) and Doramectin (DVM) etc. The effective doses of AVMs are small, but as fat-soluble drugs, AVMs in animals'bodies have long residual effect, so they are ranked as highly toxic compound by WHO. AVMs residue in animal tissues has been one of the key monitored objects in veterinary drug residue study for long time.Many physical and chemical methods to detect residue of IVM have been established at home and abroad. Some methods are precise and sensitive,but not suitable for large batch samples'screening, because of their complication, long time consuming, big cost and high technical request. ELISA technique is gradually being used to detect the residues of medicine,as a method which is sensitive, fast and powerful specificity. For exploring a method that can detect residue of Ivermectin fast and effectively, we composed man-made antigen, prepared anti-ivermectin monoclonal antibody, finally, established ELISA method to detect residues of ivermectin in this study,using monoclonal antibody technique and ELISA technique.The hapten, synthesized by carbodiimiding, was coupled to carrier protein by way of EDC's method, and the complete antigen IVM-BSA and IVM-OVA were prepared. The conjugates were demonstrated to be successful by UV-scaning, and the coupling ratio of IVM-BSA and IVM-OVA were 21:1 and 16:1 respectively.Two man-made antigens of ivermectin were synthesized by EDC's method.We used one of the antigens named IVM-BSA as an immune antigen.Then a hybridoma cell line (6A9) which could excrete anti-ivermectin monoclonal antibody steadily was gained by hybridoma's technique.The titer of abdominal dropsy we got was 1:32000, the saturation of protein was 19.9mg/mL; and the cross-reactivity with tylosin, Erythromycin, acetylerythromycin was all under 0.5%. The cross-reactivity with Avermectin was 20%.The CiELISA's method was established by the monoclonal antibody in the abdominal dropsy which was got by injecting hybridoma cells named 6A9 into BALB/c mouse. The concrete method was that,the coating antigen was attenuated by 1:4000, the monoclonal antibody in the abdominal dropsy was attenuated by 1.8000,and the concentration of drug was controlled between 5 and 2000ng/mL.The standard curve equation was got as y =0.0725x - 0.795(R2=0.9874).The correlate parameters of this equation were: IC50 at 141.25ng/mL; LOD under 5ng/mL; the limit of detection at 9.25ng/mL.This method was initially applied in the addtion and reclamation test of the liver tissue and muscle tissue of swine.The sample was to be determined after pre-processing. The intervention disappeared when the extraction of liver and muscle sample was diluted 4 times.The standard curve equation was Y=0.2019x - 2.1081 between 5~5000ng/mL,that IC50 was 5ng/g.The recovery ratio were between 65.8%～100% when adding 200,1000 and 5000ng/mL Ivermectin to the liver tissue and muscle tissue of swine. The intraassay coefficient of variation was between 3.82%～6.74%, and the interassay coefficient of variation was between 4.33%～9.42%.
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